Undeterred by Israeli Prime Minister Benjamin Netanyahu's scathing speech against an Iran nuclear deal, U.S. and Iranian negotiators have resumed work on an agreement meant to crimp Iran's atomic program in exchange for sanctions relief.

With an end-of-month deadline looming to complete a framework accord, U.S. Secretary of State John Kerry and Iranian Foreign Minister Mohammad Javad Zarif sat down Wednesday in the Swiss resort of Montreux for their third meeting this week to hash out details of an emerging pact. On Tuesday in Washington, Netanyahu told Congress that the agreement taking shape is dangerous and would allow Iran the ability to develop nuclear weapons.

U.S. officials led by President Barack Obama have criticized Netanyahu for not presenting any viable alternative to preventing Iran from getting the bomb.